1. Field of the Invention
The present invention relates generally to coverings for architectural openings and more specifically to a limit stop adapted to limit the retracting rotation of a roller on which a shade material is mounted.
2. Description of the Relevant Art
Generally, window coverings have various mechanical means for controlling the upper and lower positions of the fabric sheeting materials used in the covering. Such mechanical means is commonly referred to as a limit stop. The limit stop ensures that the fabric materials of the window covering do not traverse into the headrail more than intended, nor does it descend beyond the measured drop of the fabric. By way of example, window shade products generally use a ratchet and pawl device to stop the fabric from winding too far into the upper portion of the window. In another example, a ball stop may be attached to the operating cord to prevent the cord from traveling into the operating system beyond its design, thus preventing the fabric from wedging into the headrail. Regardless of the type of covering, it is beneficial to the operation of the window covering that some type of limit stop be installed in the system for the typical window covering to operate easily and efficiently regardless of whether it is an upper or lower limit stop.
In one limit stop known in the trade, first and second pivotally connected elements are utilized wherein the first element is attached to the rear edge of the headrail and the second element is pivotally connected to the first element so as to ride along the shade material wrapped about a roller. Such a limit stop has not been without problems inasmuch as the hinged connection of the two elements has an objectionable noise factor and the constant contact of the second element with the shade material as well as the repetitive raising and lowering of the shade causes soiling of the fabric where the limit stop contacts the fabric.
It is to provide an improvement in limit stops and to avoid the shortcomings of prior art limit stops that the present invention has been developed.